enphase M190 inverters using power with no sun.

[Cardinal]

Hi Folks, I was doing some pre-testing of the M190 with a 165 watt panel. To check out the system I rigged a test fixture with two one amp fuses in line with the 240VAC grid line and inserted an Tektronix AC current meter in series with one of the output lines of the M190. With the panel covered up there was a 60 ma AC current draw from the M190, I uncovered the panel and in full sun I had around 620 ma AC feeding the grid. 60 ma does not seem like a lot of current, but that is 14.4 watts of wasted energy, time 10 units and your burning 144 watts when the sun is not shinning. Has any one seen similar results? I called Enphase, but they were not much help just commenting that they do draw some power. To solve the issue I think I will build a solar sensor that will control A SSR (solid state relay) and turn the inverts off when there is no sun and also control the tracking system when "O" sole isn't shinning

[Mike90250]

Right, all grid-interactive inverters burn power when in standby. They have to monitor the Solar PV, to see when the sun comes up, and they monitor the grid, to make sure its healthy before engaging the inverter. However, one would think that the micro inverters would be better, I think the large multi KW inverters, are in the 10's of watts, which seems a lot better than a roof full of these power "suckers". Just be sure your SSR can handle the full string of inverters load at noon. You may have to give it +- 20 minutes to allow each inverter to download it's data to the local powerline comms/ethernet interface box at the end of the day.
mike